1. Field
This disclosure relates generally to radio, and more specifically, to a radio receiver having a channel equalizer and method therefor.
2. Related Art
A constant modulus algorithm (CMA) is commonly used to provide a channel equalizer function in a digital FM (frequency modulation) receiver. The channel equalizer is used to correct or mitigate the effects of multi-path noise or adjacent channel interference. However, in some cases, the CMA can cause unintended effects in the FM receiver. For example, single-frequency tones (spurs) may be generated within the frequency band of interest by defects in an RF (radio frequency) front-end. Also, spurs may be generated by the switching of an operating class D digital amplifier. If the spurs have a greater amplitude than the desired FM signal (signal-of-interest or SOI), the CMA based channel equalizer may lock onto the spurs while suppressing the SOI.
Therefore, it would be desirable to have an FM radio receiver that removes the spurs while still having the ability to equalize a relatively wide band SOI.